Cognitive behaviour therapy (CBT) for chronic fatigue syndrome (CFS) leads to a significant decrease in CFS-related symptoms and disability. The primary objective of this study was to explore whether partners’ solicitous responses and patients’ and partners’ perceived relationship satisfaction had an effect on treatment outcome.

The treatment outcome of a cohort of 204 consecutively referred patients treated with CBT was analysed. At baseline, CFS patients completed the Maudsley Marital Questionnaire. The Checklist Individual Strength subscale Fatigue and the Sickness Impact Profile total scores completed by CFS patients post-treatment were used as measures of clinically significant improvement. Partners completed the Family Response Questionnaire, the Maudsley Marital Questionnaire, the Brief Illness Perception Questionnaire, and the Causal Attribution List. Logistic regression analyses were performed with clinically significant improvement in fatigue and disability as dependent variables and scores on questionnaires at baseline as predictors.

Solicitous responses of the partner were associated with less clinically significant improvement in fatigue and disability. Partners more often reported solicitous responses when they perceived CFS as a severe condition. Patients’ relationship dissatisfaction was negatively associated with clinically significant improvement in fatigue.

Partners’ solicitous responses and illness perceptions at the start of the therapy can negatively affect the outcome of CBT for CFS. We emphasize the importance of addressing this in therapy.